A laminectomy is a surgical procedure performed on the spine to relieve pressure on the spinal cord or one or more nerves. Pressure on the spinal cord or on a nerve can cause various symptoms, such as neck and back pain and/or radicular pain in the arms and legs. Upon removing the lamina, the compressed nerves can be exposed and pressure on the nerves can be further relieved by removing the source of compression, such as a portion of the disc, a disc fragment, a tumor, or a rough protrusion of bone.
Spinal fixation procedures can be performed in conjunction with a laminectomy to align and/or fix desired relationships between adjacent vertebral bodies. Such spinal fixation procedures typically include positioning a plurality of spinal fixation assemblies within target vertebrae. These assemblies usually include a threaded shank portion configured to be disposed (e.g., threaded) within a vertebra and a proximal receiver head configured to receive and secure some type of spinal stabilization element (e.g., a rigid or flexible rod, a cable, a biological construct, a tether, a tape, etc.). Once these assemblies are disposed within the desired vertebrae, a spinal stabilization rod can be positioned and secured within the receiver heads thereby allowing the rod to extend along a length of the patient's spinal column. Once secured as such, the installed spinal stabilization rod can hold the vertebrae in the desired spatial relationship, either until desired healing or spinal fusion has taken place, or for some longer period of time.
Due to the intricacies of working in proximity to the spinal column, such laminectomies and spinal fixation procedures can cause serious patient injury and/or significant patient trauma. For example, such procedures typically require spinal fixation assemblies to be delivered directly (i.e., substantially perpendicular to the midline of the patient's spinal column) into a lateral mass or pedicle of a target vertebra. In light of this trajectory, significant amounts of muscle and tissue must be stripped from the treatment site due to the relatively large distance between the lateral mass/pedicle entry point and the midline of the spinal column. Also, any slight miscalculation in the delivery trajectory can result in penetration of a distal portion of the assembly (e.g., a pointed tip) into the spinal canal or the foramina of the exiting nerve root thereby causing significant patient injury. As a further disadvantage, the limited bone mass and/or bone density typically found in the lateral mass portion of a vertebra significantly limits the amount of area available for contacting the fixation assembly thereby hindering the ability to effectively position the fixation assembly within the vertebra.
Thus, there remains a need for methods and systems for spinal decompression and/or for securely positioning fixation assemblies within target vertebrae while also minimizing the risk of injury and associated patient trauma.